BP Brews Up an Ethanol Breakthrough with Engineered Yeast

BP Brews Up an Ethanol Breakthrough with Engineered Yeast

A BP-backed research project has produced a variety of yeast designed to process cellulosic material into ethanol more effectively than before.

Researchers at the University of Illinois, in conjunction with Lawrence Berkeley National Laboratory, Seoul National University, and the University of California, have engineered a yeast strain that can process two types of sugar at once.

The researchers, supported by the BP-funded Energy Biosciences Institute, claim the yeast can process glucose, a common type of sugar, along with xylose, which is a wood sugar that yeasts typically process far more slowly, if at all.

The few yeasts that can process xylose do so only after processing the glucose found in a material. This serial processing of sugars is one of the factors leading to the relatively slow processing of cellulosic materials such as woody biomass and other organic waste materials.

However, the engineered yeast processes sugars differently to conventional yeasts. Traditionally, a yeast will convert cellobiose -- a sugar found on plant cell walls which is a precursor to glucose -- into glucose before transporting it into the yeast cell and breaking it down. The engineered yeast instead transports the cellobiose into the cell and converts it to glucose there. This process enables the yeast's glucose transporters to focus on transporting xylose inside the cell.

This process of co-fermentation means that two separate fermentation stages are no longer needed, and eliminates the need for a cellobiose-degrading enzyme to biomass mixtures before processing.

The researchers said the yeast can double the amount of sugar processed in a set time period, significantly accelerating the speed at which cellulosic ethanol is produced. They added that the process could be commercialized "very soon."

This article originally appeared on BusinessGreen, and is reprinted with permission.